In recent years, a light-emitting diode (LED) element, which is a semiconductor element, is widely used for backlight, lighting, etc., of a color display device, a light bulb, lighting equipment, lighting system, a headlamp of a vehicle and so on.
A lighting device including a plurality of LED elements arranged in a mounting area has been proposed, for example, Patent Document 1: Japanese Unexamined Patent Publication (Kokai) No. 2010-287657.
Hereinafter, a light-emitting portion 1 of a conventional light-emitting module shown in FIG. 1 is briefly explained. The light-emitting elements 101 each including a pair of element electrodes are disposed in columns in a zigzag arrangement on light-reflecting layers or separated mounting areas 102a-102d. At least some of the light-emitting elements 101 are electrically connected to one another in series by bonding wires 108 and electrically connected to electrical conductors 103a, 103b, 104a, 104b, and/or 104c at both ends of each column.